This book shows the main aspects related to SOFC based hybrid systems and possible solutions to some technical problems coming from component integration. After an introduction related to the state-of-the-art of these plants, attention is focused on the fuel cell technology for hybrid system applications including the main components necessary to operate with standard fuels. Then, the book presents micro gas turbine (mgt) technology for hybrid system applications, especially considering several issues (not completely solved) related to the coupling between SOFCs and mgts. Great attention is devoted to dynamic issues, including control system aspects, to avoid risk conditions taking into account all the system constraints. For this reason, it is essential to analyze these systems with computational models and experimental plants. Several computational models, appropriate for design and development as well as performance analysis including off design behavior are presented in this book for analyses at both component and system levels.